ABSTRACT In this paper, the hydrodynamic performance of cylindrical buoy-rope- drum wave power generation device was studied. Firstly, the three-dimensional grid model of buoy-rope-drum wave power generation device was established. The hydrodynamic performance of the whole cylindrical buoy-rope-drum wave power generation device was calculated by using computational fluid dynamics method and fluent combined with C++ programming. The motion of the floating body was realized by using dynamic grid, and the structural heave and sway curves were obtained. In addition, the vortex induced motion of the cylindrical buoy-rope-drum wave power generation device was numerically calculated in this paper, and the method of restraining the vortex induced motion of the cylinder by the spiral side plate suitable for this structure was calculated and analyzed. Three side plate heights H0.1D, H0.2D,H0.3D, the drag coefficient and vibration displacement of cylindrical wave power generation device with spiral side plate were calculated with different pitch.
INTRODUCTION Wave energy power generation devices convert the kinetic energy and potential energy of the ocean floating structure moving with the wave into electric energy. According to the research and development results of different research institutions, there are many kinds of wave energy power generation devices, but many of them adopt cylindrical structure or improved structure based on cylinder. The single heave point absorption wave energy power generation device developed by Ohio State University was composed of a cylinder foundation and an oscillating float. The cylinder foundation was connected with the seabed through a rigid cable, and the float moves relative to the cylinder foundation. Wavebob was a double body heave point absorption wave power generation device developed by Ireland. It consists of two coaxial cylindrical floating bodies. The lower cylindrical floating body is completely submerged in the sea. The heave motion of the floating body is the most concerned of the device. Caska (2008) and others studied the hydrodynamic performance of a cylindrical float hinged at the bottom on the seafloor by using the analytical method. When calculating the motion of the float in regular waves, they used the first-order nonlinear formula and found that the nonlinear drag force greatly affected the motion performance of the float. Mehdi et al. (2013) designed a point suction wave energy device located in assaluye port, Iran based on the linear wave theory. The research found that changing the flat bottom cylindrical float into a vertebral float significantly reduced the heave damping and increased the heave amplitude of the float. Guo (2016) took the typical point absorption wave energy device as the research object, establishes the hydrodynamic model of the float in the wave energy device by combining theoretical analysis and numerical simulation, and studies the motion, load, energy absorption characteristics, free surface deformation and flow field of the typical wave energy device. Qi et al. (2015) designed three kinds of mouth section three screw head spiral guide plates with pitch / diameter ratio for cylinders with high mass damping ratio, and carried out wind tunnel experiments to study its suppression effect on vortex induced vibration. Xu et al. (2018) studied the suppression effect of spiral plates on vortex induced vibration of cylinders in an indoor towing tank.